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    Because tests often dominates the execution time, a Hudson best practice
    involves splitting test executions into different jobs, possibly in multiple
    different jobs.

    <p>
    When you do that, setting test aggregation is a convenient way of
    collecting all the
    test results from such downstream test jobs and display it along with the
    build that they are testing. In this way, people can see the overall test
    status of the given build quickly.
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